Liams



A. C. McWILLlAMS.

FILM SOCKET FORSERIES LAMPS.

APPLICATION FIEED IULYH. 1911.

1,3 1 4,008 Patented Aug. 26, 1919. 4

2 SHEETS-SHEET 1- 412 l *Ill A. c. McjwlLLlAms; FILM SOCKET FOR SERIESLAMPS. APPLICATION min ;uL Y n, 1912.

,3 14,008 v Patented 26, 1919.

2 SH -SHEET.2.

UNITED STATES PATENT ()FFIQE.

ARTHUR C. MCWILLIAMS, OF CHICAGO, ILLINOIS, ASSIGNOR TO GEORGE CUTTERCOMPANY, SOUTH BEND, INDIANA, A CORPORATION OF INDIANA.

FILM-SOCKET FOR SERIES LAMPS.

Specification of Letters latent. Patented Aug, 26, 1919.

Application filed July 11, 1917. Serial No. 179,815.

To all whom it may concern:

Be it known that I, ARTHUR C. MoWIL- LIAMS, citizen of the UnitedStates, residing at Chicago, Illinois, have invented certain new anduseful Improvements in Film- Sockets for Series Lamps: and "I do herebydeclare the following to be a full, clear, and exact description oftheinvention, such. as will enable others skilled in the art to which itappertains to make and use the same.

In its general aspects, my inventionrelates to sockets or receptaclesfor series circuits and aims to provide advantageous means formaintaining the circuit closed at all times, regardless of the rupturingof a portion of the circuit in an attached socket or other auxiliaryappliance or of the bodily removal of such auxiliary appliance. the sameaspect, it also aims to provide simple and positive means forinterlocking the socket with the detachable appliance to prevent anaccidental separation. thereof, while permitting the same to be manuallyseparated or joined at will; also, to provide simple means forintroducing a puncturable dielectric at a desirable point in thecircuit, for affording convenient access to the dielectric and forquicklyrestoring a punctured dielectric to operative condition withoutmoving the latter. I

In another aspect, my invention relates to means for positively limitingthe voltage required for puncturing the dielectric safety element in afilm-protected lamp socket, for quickly attaching or detaching the samewithout materially afi'ecting this puncture voltage, and for quicklyshifting the puncture points on a given dielectric element to utilizethe latter repeatedly without detaching this element from its mounting.

More particularly, my invention relates to sockets for series lamps andaims to provide a common carrier as to positively interlock with thesocket while automatically opening an otherwise closed shunt around thelamp and while permitting the lamp itself to be freely rotated withrespect to the socket; to provide common means for making one of theelectrical connections from the socket to the lamp and to one of thedielectrically separated elements; to afford a simple, effective andeasily manipulated mounting for the dielectric; to define puncturepoints upon the latter and to permit these puncture points to beinstantly shifted without the use of tools and without moving or eventouching the dielectric; to provide a substantially constant pressure ofthe mounting against the dielectric, thereby maintaining the puncturevoltage below a desired maximum, and to provide a generally simple,compact and cheap series socket construction. Still other ob]ects willappear from the following specification and from the-drawings, whichdrawings, however, are understood as illustrating only one embodiment ofmy invention.

In the drawings, Figure 1 is a vertical and for the most part centralsection through a series socket embodying my invention, with a lamp inplace.

Fig. 2 is a transverse section through the same, taken along the line 22of Fig. 1 and looking downward.

Fig. 3 is a transverse section, looking upward from the line 33 of Fig.1.

Fig. 4.- is a perspective view of the. upper portion of the lamp withthe film-carrier and film in position on the lamp base.

Fig 5 is a perspective view of aspring fingered fork of the socketproper.

Fig. 6 is an enlarged perspective view of the detachable film-pressingcollar of Figs. 1 and 1.

Fig. 7 is a fragmentary section ofa socket showing another shape of thelive contact terminal.

Fig. 8 is a perspective view of an independent gripper finger, a numberof which may be used in place of the fork of Fig. 5.

In L employing my invention on series lighting circuit the socketembodying the same may desirably have a porcelain base 1 integral with aporcelain collar 2, and may have on its base wire terminals 3 and 4 asshown in Fig. 1. Secured to these terminals and contacting with eachother when the lamp is removed from the socket are line closing contacts5 and 6, of which the former is here shown as extending near one side'ofthe bore of the collar 2 but terminated short of the mouth of thelatter, while the companion contact 6 extends substantially transverselyof the socket and is continuously forced by its own resiliency towardthe contact member 5. The base 1 also carries a plurality of arms 7 allextending within the bore of the collar 2 toward the mouth of the latterand all continuously pressed inward by their own resiliency, which armsmay be carried by a common base, as in Figs. 1 and 5, 01' may beindependent as in Fig. 8. These arms or gripper fingers 7 all have bendssubstantially in circumferentialalinement about the axis of the collar2, thereby affording shoulders for jointly engaging a bead 8 on aclamp-cap 9. The contact 5 desirably is shorter than the arms 7 but sodisposed as to engage the side of the clamp-cap 9 when the latter isthus interlocked with the arms 7. This clamp-cap fits over the screwbase 10 of a standard incandescent lamp 11 and is clamped u)on saidbaseby the screw 1:2

drawings.

Interposed between this clamp ring 17 and l the top of the clamp-cap isa dielectric, de-

sirably in the form of a flat ring of cloth or paper, which dielectricis thus clamped be tween the said clamp-cap and the camactuated ring 17.However, instead of providing the latter ring 17 with an unbroken flatcontact surface and thus permitting the dielectric to he punctured atany point whatever, I provide substantially conical tits 18 on thisring, thus defining definite puncture points in the dielectric-(or film,as the latter is commonly called in series lighting practice).Consequently, if the lamp burns out while in position, the-current willjump through the film at one or more of these definitely located points,leaving the remainder of the film ring substantially unscorched. Then,upon withdrawing the lamp from the socket and thereby affording accessto the clampcap and the parts carried by the latter, the clamping ring17 can readily be raised slightly and then rotated sufficiently to causethe tits 18 to bear on fresh portions of the film, thereby resetting thefilm without moving or touching the latter;

In practice, I have found that a film of the small sizeeasilyspositioned over an ordinary lamp base can thus be used. a numberof times, and since the film itself need not be moved or in any Waydisturbed while resetting the film clamp, I avoid the tearing of thefilm which has been so common where the attempt was made to move a filmwhich had been partly scorched to adjoining parts by the puncturing sark. Moreover, I have found that by suita 1y pointing the tits 18 andsuitably proportionlngthe cooperating spring fingers 16 and the slope ofthe cam surface on the Stud 14." I can effectively keep down thevoltagerequired for puncturing the film, being thus able to reduce it toseveral hundred Volts less than that required for the same film with thefilm holding parts of the series sockets heretofore in use.Consequently, I avoid the risk of having the voltage rise sufficientlywith the burning out of one lamp to affect other lamps on the circuitalsoa point of particular importance with the modern nitrogen filledlamps in view of the higher temperatures at which they operate.

At the same time, it will be obvious from the drawings that theclamp-cap 9 can be instantly slipped over and attached to the base of anordinaryEdison base lamp, thereby making this clamp cap substantiallyintegral with the lamp. Then, on slipping this cap into the socket, thebead 8 readily engages the spring fingers, thereby securely interlockingthe lamp with the socket so that it cannot jar loose as in the case ofscrewthreaded sockets and parts threaded thereinto. When thu positioned,any rotating of the lamp about its axis (as when cleaning the same)cannot affect the security of its position, and there is no danger ofits graduall y creeping out of the socket. Meanwhile the stud 1 bypressing against the line contact (3 (which contact is suitably spacedfrom the shoulder on the line contact 5 to give this effect) holds theautomatic line-closing contacts apart, yet permits them to contactinstantly when the lamp is removed from the socket. Moreover, since theresistance of all the sloping shoulders engaging the bead 8 must {beovercome, the lamp must be pulled out with some speed, so that the saidlineclosing contacts engage each other too rapidly to permit the arcingwhich has proven destructive in corresponding portions of series socketshaving threadedly connected parts permitting a slot withdrawal of thelamp and of the film-carrier. Likewise, when replacing the film-carrierand the lamps on which it is mounted, the joint resistance of the springfingers 7 insure a quick snapping of the film-carrier into its to anyone accidentally reaching the mouth of the socket.

Wheirthe film has been used a sufficient number of times to'effectivelyutilize it, the film-ring 17 can readily be pulled off the stud 14 andthe film itself replaced with another. To avoid a change in theeffective pressure dueto a possible bending or distorting of the fiatportion of the ring 17, I

preferably dispose the tits 18 substantially in line with the springfingers 16. However, I do not wish to be limited to this or otherdetails of the construction herein disclosed,

:leaving the gripping of the latter entirely to the spring fingers 7 Iclaim s my invention: 1. Means for shuntingthe filament of a seriesincandescent lamp, comprising a metal member secured to one terminal'ofthe lamp, a conductor carried byand insulated from the said member andcontacting-with the other lamp terminal, and an auxiliary member mounteddirectly on the said conductor and disposed for clamping adielectricbetween itself and the said metal member, the conductor havingan enlarged head and the auxiliary member having a resilient portionadapted to be snapped over the said head.

2. Means for shunting the filament of a series incandescent lamp,comprising a metal member secured to one terminal of the lamp, aconductor carried by and insulated from the said member and contactingwith the other lamp terminal, and an auxiliary member mounted directlyon the said conductor and disposed for clamping a dielectric betweenitself and the said metal member, the auxiliary member being rotatablewith respect to the metal member and one of the said membersbeingequipped with a projection directed toward the other member to define apuncture point in the dielectric.

3. Means for shunting the filament of a series incandescent lamp,comprising a metal member secured to one terminal of the lamp, aconductor carried by and insulated from the said member and.cont-acting'with the other lamp termin'al, and an auxiliary membermounted directly on the said conductor and disposed for clamping adielectric between itself and the said metal member, the

auxiliary member being rotatable with re-,

spect to the metal member, andone of the said members being equippedwith a plurality of symmetrically disposed projections directed towardthe other member to define puncture points in the dielectric.

'4. In a lamp and socket combination, a metal cap substantially incasingthe lamp shell and electrically connecting one terminal of'the lampdirect to a line terminaL'a contact member carried byfibut insulatedfrom the cap and connecting the otherlamP terminal to the circuit, andan auxiliary conducting member detachably disposed be- V respectivelycontacting with the lam tween the cap and the auxiliary conductingmember and rotatable with respect to'the cap.

5. In a lamp and socket combination, a metal cap substantially incasingthe lamp shell and electrically connecting one terminal of the lampdirect to a line terminal, a contact member carried by but insulatedfrom the cap and connecting the other lamp terminal to the circuit, and.an auxiliary conducting member detachably disposed between the cap andthe contact member and rotatable with respect to the cap, the auxiliaryconducting member being rotatable with respect to the contact member.

' 6. In a lamp and socket combination, a metal cap substantiallyincasing the lamp shell and electrically connecting one terminal ofthelamp direct to a line terminal, a

'contact member carried by but insulated from the cap and connecting theother lamp terminal to the circuit, and an auxiliary conducting memberdetachably disposed between the cap and the contact member and rotatablewith respect to the cap, one of the elements between which thedielectric is disposed being equipped with puncture-defining projectlonsdirected toward the other of said elements.

7. Means for shunting the filament of a series incandescent lamp,comprising a metal member secured to one terminal of thelamp, aconductor carried byifand insulated from the said member and contactingwith the other lamp terminal, andan auxiliary member mounted directlyoirjthe said conductor and disposed for clampinga dielectric betweenitself and the said metal member, the auxiliary member having resilientportions and the said conductor being so shaped that clampingdisposition merely by the engagement of the said resilient portions withsaid conductor- 8. Filament-shunting means for an incandescent lamp,comprising a pairof metal members associated with the lamp base andterminals on the latter, a puncturable ielectrio disposed. on thesurface of one of the said members, an auxiliary metal elementinterposed between the dielectric and the other metal member, and cammeans associated with said auxiliary element and the last named memberfor causing the auxiliary element to press against the dielectric.

9. In a series electric lighting system, the combination with alamp'and' a. socket, of an annular metal element electrically connectedto one lamp terminal, anannular dielectric disposed on the said annularelement, a metal stem axial of the dielectric and electrically connectedto the other lamp terminal, and an auxiliary metal member mounted onthestem and presenting a plurality of projections spaced points to pressthe dielectric against the said annular element; the auxiliary metalmember beingarranged for manual retraction fromthe stem and rotation onthe latter, thereby permitting the said projections to successivelyengage diflferent points of the dielectric.

10.. In a series electric lighting system, the combination with a lamp,of a pair of annular elements disposed for'jointly shunting the lamp,and an annular and puncturable dielectric disposed between saidelements, the said annular elements being relatively rotatable.

11. In a series electric lighting system, the

combination with a lamp, of a'pair of an nular elements disposed forjointly shunting the lamp, and an annular and puncturable dielectricdisposed between said elements, the said annular elements beingrelatively.

rotatable and one thereof being equipped.

with puncture-defining projections directed toward the other thereof.

12. In a series electric lighting system,

base, a dielectric disposed upon said annular end, and clamping meanscarried by the stem and pressing the dielectric against said annularend, the clamping means being movable upon the stem so that the same maybe brought to press successively against different portions of thedielectric.

13. For use on a series circuit, a terminal carrier; acircuit-connecting appliance therefor equipped with means forsimultaneously gripping the carrier, making the circuit connectionsthereto and opening a shunt around said connections; the said meansincluding a stem secured tothe carrier and a shunting switch memberengaged by the stem to open the switch; and auxiliary means for shuntingthe said connections, the said auxiliary means comprising a conductingelement concentric with the' stem, a resilient element rotatably mountedon the stem, and a dielectric clamped between the said elements.

14. For use on a series circuit, a terminal carrier; a switchin sockettherefor, and an intermediary mem er rigidly clamped to the terminalcarrier and arranged for methus gripped; and auxiliary shunting meanscomprising. a clamping-member rotatably mounted on the last namedconductor and a dielectric clamped between the two conductors.

.115. In a socket for a series lamp, the combination with a pair ofcurrent conducting members normally forming part of the cirsuit to thelamp,-oi' a uncturable dielectric disposed upon one of the said members,and means connected to the other member and engaging the dielectric ndadapted to shunt the circuit upon a puncturing of the latter,

the said means being movable to bring the same into engagement withdifferent parts of the dielectric without moving the latter. I

16. For use with an Edison base series lamp and a socket havin aself-closing line switch and a plurality 0% spring fingers, anintermediary member carried by the lamp and comprising a substantiallysingle-piece cup-shaped metal element housing the screwshell of the lampand afibrding direct electrical connection from the latter to oneterminal of the line switch and having formations interlocking with thespring fingers to hold the intermediary member and the lamp inpredetermined relation to the socket, a conductor carried by andinsulated from the cup-shaped element and disposed for atfordin directelectrical connection between the axial lamp terminal and the otherterminal of the line switch and for opening the line switch, an annulardielectric disposed

